Organic electroluminescent materials and devices

A compound of formula Ir(LA)x(LB)y(LC)z, wherein:

• each of x and y is independently 1 or 2;
• z is 0 or 1;
• and x+y+z=3;
• first ligand LA comprises a structure of Formula I,
• ligand LB comprises a structure of Formula II,
• ligand LC is a bidentate ligand;
• moiety A is a monocyclic ring or a polycyclic fused ring system, wherein the monocyclic ring or each ring of the polycyclic fused ring system is independently a 5-membered to 10-membered carbocyclic or heterocyclic ring;
• each of X1 to X14 is independently C or N;
• Y is selected from the group consisting of O, S, Se, NRY, BRY, BRYRY′, PRY, PRYRY′, CRY, C═O, C═NRY, C═CRYRY′, C═S, C═Se, CRYRY′, S═O, SO2, P(O)RY, SiRYRY′, and GeRYRY′;
• each of RA, RB, RC, RD, and RE independently represents mono to the maximum allowable substitutions, or no substitutions;
• each RA, RB, RC, RD, RE, RY, and RY′ is independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof;
• each of R1, R2, and R3 is independently an alkyl, a partially or fully deuterated alkyl, a partially or fully fluorinated alkyl, a cycloalkyl, a partially or fully deuterated cycloalkyl, or a partially or fully fluorinated cycloalkyl;
• RD1 is a cycloalkyl group or an alkyl group comprising at least two C atoms and is optionally partially or fully deuterated;
• and
• any two substituents may be joined or fused to form a ring.